Question: Simplify the following expression: $z = \dfrac{y}{2} + \dfrac{3y}{8}$
Explanation: In order to add expressions, they must have a common denominator. The smallest common denominator is the least common multiple of $2$ and $8$ $\lcm(2, 8) = 8$ $ z = \dfrac{4}{4} \cdot \dfrac{y}{2} + \dfrac{1}{1} \cdot \dfrac{3y}{8} $ $z = \dfrac{4y}{8} + \dfrac{3y}{8}$ $z = \dfrac{4y +3y}{8}$ $z = \dfrac{7y}{8}$